Url Rewriting
We all know and repsect the voodoo that is apache mod_rewrite, the superb apache mod that allows one to redirect/rewite urls, silently redirecting nice SEO friendly URLS to
standard query string types e.g.:
http://www.coolsite.com/news/coolstuff/new-url-rewriting-mod/ -> http://www.coolsite.com/?pageid=123871&catid=2432
Moving Pages
One handy use of mod rewrite is when you re-organise your sites url structure, it’s ability create redirects for all the old urls with regular expressions can be a real life saver as all your previous incoming links may end up with ghastly 404 page not found messages. This is especially useful when simple 301 Redirects aren’t powefull enough
One Caveat however, is that mod_rewrite can’t rewrite query strings with the normal RewriteRule. for example:
Works:
RewriteEngine On
RewriteRule ^cakes/ /puddings/cakes/
Doesn’t work
RewriteEngine On
RewriteRule ^cakes/?cakeid=12 /puddings/cakes/sponge/
Instead, one has to use the RewriteCond to catch the Query String:
RewriteEngine On
RewriteCond %{QUERY_STRING} cakeid=12
RewriteRule ^cakes/ /puddings/cakes/sponge/
So in detail, to redirect:
http://www.mysite.com/url/path/?some=query&other=queries&etc
to
http://www.mysite.com/new_url/
RewriteEngine On
RewriteCond %{QUERY_STRING} some=query&other=queries&etc
RewriteRule ^url/path/ /new_url/
Ref:
http://httpd.apache.org/docs/1.3/misc/rewriteguide.html
don’t forget [L]at the end (Last rule)
That’s a good point sir!
Rule becomes
RewriteRule ^url/path/ /new_url/ [L]I’d also suggest us of a 301 redirect with [R=301]:
Rule becomes:
RewriteRule ^url/path/ /new_url/ [L,R=301]